Ferguson 421 UXL - UK Vintage Radio Repair and Restoration Discussion Forum

Ferguson 2000 · 27th Jul 2021, 7:18 pm

Hi,

I have been asked to repair the above radio by a collector, after I have repaired his Blaupunkt!

The radio is not one that I have seen before and I cannot find any reference to it using Google. The cabinet is a sort of mid maroon colour as a few Ferguson's were, valves are used including a tuning indicator and the back shows allegiance to Thorn.

Has anyone come across one of these?

Best wishes,

Geoffrey.

dazzlevision · 27th Jul 2021, 7:50 pm

That's an export market set, as it can operate on 110 or 220-240V mains. It may not have Long Wave, as this is (was) only used in Europe. The U probably means ac/dc mains (as per UK market Ferguson radios) and the X means export.

You may find it very difficult to get any service data as a result, although it may have a fairly close resemblance to a UK market model of that time.

A photo of the whole chassis may help ID a similar UK market set.

Ferguson 2000 · 27th Jul 2021, 10:29 pm

Hi dazzlevision,

Many thanks for your reply and information, I will pass it on when I take the Blaupunkt back, hopefully working. Down to my lock up garage to see if I have an ECH81 tomorrow as it has VHF but no Long or Medium wave, it had increasing positive volts on the grid of the oscillator which turned out to be a disconnected wire on a tuning coil, stable but very low negative volts after repairing that.

I think it is decades since I last repaired a valve radio.

Many thanks for the information,

Geoffrey.

Ferguson 2000 · 31st Jul 2021, 3:00 pm

The Blaupunkt Barcelona has gone back and the Ferguson 421 UXL is on the bench.

It uses a UL84 output valve and the Cathode Resistor has gone very high in value about 2,000 ohms. Any suggestions for the right value? The colour value rings are badly burnt but the third one will be brown and the first two are burnt red or burnt orange. I think that Ferguson made other sets using the UL84 so perhaps the value will be the same.

Many thanks.

dazzlevision · 31st Jul 2021, 4:42 pm

Quote:

Originally Posted by dazzlevision

A photo of the whole chassis may help ID a similar UK market set.

A photo of the WHOLE chassis may help ID a similar UK market set!

Techman · 31st Jul 2021, 5:44 pm

You'll need to ask yourself why that resistor burnt up - probably a bad coupling capacitor to the grid of that valve. I guess the output transformer has survived (it sometimes doesn't) as you say it's working on VHF. Replace the grid coupling capacitor before powering it up again. You should be able to work out what the cathode resistor should be or look at what's used in similar output stages using that valve and then check anode current against quoted valve data.

I guess you might need a UCH81 and not an ECH81.

Nuvistor · 1st Aug 2021, 11:29 am

Checked a couple of AC/DC Ferguson’s that use a UL84 valve, cathode bias resistors were 270 ohm in one and 330 ohm in the other, 330 Ohm would be a safe starting point.
Agree the need to check why the original resistor burnt out.

Ferguson 2000 · 5th Aug 2021, 3:37 pm

Hi,

As requested photographs of set, owner has the tuning scale which he is cleaning up.

Mention of an ECH81 was for the Blaupunkt Barcelona which only had VHF being repaired for the same collector, the Ferguson does not have VHF only Medium and Short Wave.

The fault was a loud crackling noise, the HT showed only a very tiny variation, disconnecting the capacitor to the grid of the UL84 output valve did not alter the fault but the cathode volts seemed a bit high at 20 Volts. Cold checks showed the cathode bias resistor to be high at 2 k ohms. I have put a 330 ohm in and replaced the cathode electrolytic which had been replaced before, grid coupling capacitor read OK so I put it on test. After an hour or so the cathode volts went from 15 to 18 volts so after much searching I found a 0.1 uF 400 volt to replace the grid coupling capacitor, cathode volts still went up and the grid went from 0 to +3 volts, so I need a new valve. Surprisingly the output was not distorted.

Off to my lock up garage, 4 UL41 but no UL84, found a couple of Eddystone radio sets. I will ask the owner if he has one.

Many thanks for your suggestions.

27th Jul 2021, 7:18 pm	#1
Ferguson 2000 Tetrode Join Date: Jun 2008 Location: Stratford upon Avon, Warwickshire, UK. Posts: 80	Ferguson 421 UXL Hi, I have been asked to repair the above radio by a collector, after I have repaired his Blaupunkt! The radio is not one that I have seen before and I cannot find any reference to it using Google. The cabinet is a sort of mid maroon colour as a few Ferguson's were, valves are used including a tuning indicator and the back shows allegiance to Thorn. Has anyone come across one of these? Best wishes, Geoffrey. Attached Thumbnails __________________ Best wishes, Geoffrey.

27th Jul 2021, 7:50 pm	#2
dazzlevision Dekatron Join Date: Sep 2003 Location: Near Swindon, North Wiltshire, UK. Posts: 3,611	Re: Ferguson 421 UXL That's an export market set, as it can operate on 110 or 220-240V mains. It may not have Long Wave, as this is (was) only used in Europe. The U probably means ac/dc mains (as per UK market Ferguson radios) and the X means export. You may find it very difficult to get any service data as a result, although it may have a fairly close resemblance to a UK market model of that time. A photo of the whole chassis may help ID a similar UK market set. Last edited by dazzlevision; 27th Jul 2021 at 8:05 pm.

27th Jul 2021, 10:29 pm	#3
Ferguson 2000 Tetrode Join Date: Jun 2008 Location: Stratford upon Avon, Warwickshire, UK. Posts: 80	Re: Ferguson 421 UXL Hi dazzlevision, Many thanks for your reply and information, I will pass it on when I take the Blaupunkt back, hopefully working. Down to my lock up garage to see if I have an ECH81 tomorrow as it has VHF but no Long or Medium wave, it had increasing positive volts on the grid of the oscillator which turned out to be a disconnected wire on a tuning coil, stable but very low negative volts after repairing that. I think it is decades since I last repaired a valve radio. Many thanks for the information, Geoffrey. __________________ Best wishes, Geoffrey.

31st Jul 2021, 3:00 pm	#4
Ferguson 2000 Tetrode Join Date: Jun 2008 Location: Stratford upon Avon, Warwickshire, UK. Posts: 80	Re: Ferguson 421 UXL The Blaupunkt Barcelona has gone back and the Ferguson 421 UXL is on the bench. It uses a UL84 output valve and the Cathode Resistor has gone very high in value about 2,000 ohms. Any suggestions for the right value? The colour value rings are badly burnt but the third one will be brown and the first two are burnt red or burnt orange. I think that Ferguson made other sets using the UL84 so perhaps the value will be the same. Many thanks. __________________ Best wishes, Geoffrey.

31st Jul 2021, 5:44 pm	#6
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: Ferguson 421 UXL You'll need to ask yourself why that resistor burnt up - probably a bad coupling capacitor to the grid of that valve. I guess the output transformer has survived (it sometimes doesn't) as you say it's working on VHF. Replace the grid coupling capacitor before powering it up again. You should be able to work out what the cathode resistor should be or look at what's used in similar output stages using that valve and then check anode current against quoted valve data. I guess you might need a UCH81 and not an ECH81.

1st Aug 2021, 11:29 am	#7
Nuvistor Dekatron Join Date: Aug 2013 Location: Wigan, Greater Manchester, UK. Posts: 9,433	Re: Ferguson 421 UXL Checked a couple of AC/DC Ferguson’s that use a UL84 valve, cathode bias resistors were 270 ohm in one and 330 ohm in the other, 330 Ohm would be a safe starting point. Agree the need to check why the original resistor burnt out. __________________ Frank

5th Aug 2021, 3:37 pm	#8
Ferguson 2000 Tetrode Join Date: Jun 2008 Location: Stratford upon Avon, Warwickshire, UK. Posts: 80	Re: Ferguson 421 UXL Hi, As requested photographs of set, owner has the tuning scale which he is cleaning up. Mention of an ECH81 was for the Blaupunkt Barcelona which only had VHF being repaired for the same collector, the Ferguson does not have VHF only Medium and Short Wave. The fault was a loud crackling noise, the HT showed only a very tiny variation, disconnecting the capacitor to the grid of the UL84 output valve did not alter the fault but the cathode volts seemed a bit high at 20 Volts. Cold checks showed the cathode bias resistor to be high at 2 k ohms. I have put a 330 ohm in and replaced the cathode electrolytic which had been replaced before, grid coupling capacitor read OK so I put it on test. After an hour or so the cathode volts went from 15 to 18 volts so after much searching I found a 0.1 uF 400 volt to replace the grid coupling capacitor, cathode volts still went up and the grid went from 0 to +3 volts, so I need a new valve. Surprisingly the output was not distorted. Off to my lock up garage, 4 UL41 but no UL84, found a couple of Eddystone radio sets. I will ask the owner if he has one. Many thanks for your suggestions. Attached Thumbnails __________________ Best wishes, Geoffrey.